Discussion Overview
The discussion revolves around troubleshooting a segmentation fault encountered when using "mpirun" to run VASP 5.2, a density functional theory (DFT) software. Participants explore various potential causes and solutions related to memory management, configuration settings, and system resources.
Discussion Character
- Technical explanation
- Debate/contested
Main Points Raised
- One participant reports a segmentation fault with a specific error message related to process rank and signal 11.
- Another participant suggests that various factors can cause segmentation faults and provides a link to a resource listing potential causes.
- A participant mentions that their INCAR file is simple, yet changing the ENCUT parameter does not resolve the issue, indicating possible configuration problems.
- Some participants propose modifying the Makefile to include specific flags to address memory issues, but this does not resolve the fault for the original poster.
- One participant notes that running a large system on a 4-core CPU leads to segmentation faults, which disappear when using a CPU with higher memory, suggesting memory limitations may be a factor.
- Another participant questions whether the RAM is full and suggests requesting more resources when submitting jobs on a cluster.
- Concerns are raised about stack overflow due to large arrays declared on the stack, with suggestions to use heap memory instead.
- Participants discuss the use of core dumps and debugging tools like gdb as potential methods for diagnosing the issue.
Areas of Agreement / Disagreement
Participants express multiple competing views regarding the causes of the segmentation fault, with no consensus on a single solution or definitive cause. Various hypotheses about memory management and system configurations are presented, but the discussion remains unresolved.
Contextual Notes
Some participants mention specific configurations and memory management techniques without reaching a conclusion on their effectiveness. There are references to the limitations of stack size and the potential need for heap memory, but these points are not universally accepted as the solution.